Coatings consisting of or resembling a diamond material have properties similar to corresponding traditional diamonds. The first property is hardness. Another significant mechanical property is a low friction coefficient. The resistance to wear is also extraordinary. Furthermore, such a coating remains unchanged in all known kinds of acids and bases. Diamond and diamond-like materials are therefore especially suited for the coating of objects subject to wear or corrosion, e.g. bearings without lubrication. A further notable factor is the high refraction index of diamonds.
In microelectronics, the high thermal capacity and thermal conductivity of diamond and diamond-like coatings provide significant advantages. To achieve higher component densities and speeds, it is necessary to reduce the structural size of integrated circuits. This makes it more difficult to remove the heat generated by the electric current, and it also means that good conductivity is more important than before.
In current practice, diamond-like coatings are produced by direct ion beam treatment, which is based on increasing the energy of ions. In direct ion beam coating, the coat is grown on the surface of the object material directly from the ion beam, from which the impurities have been removed by means of a separating magnet. The worst problem with this method is the difficulty of constructing an ion source of sufficient capacity. Another currently used method for growing a diamond coat is based on plasma-assisted vapor phase coat deposition (PAVCD). In this method, a crystal-line diamond is grown from a mixture of methane and hydrogen. Unlike the method based on the use of an energetic ion beam for growing a diamond coat, which can be implemented in room temperature, the PAVCD method requires a high temperature of the order of 800.degree. C. This is a serious disadvantage in view of the coating of conventional materials used in tools or construction.